Publicly funded joint project "GreenREX": In close collaboration with the Fraunhofer ICT, KSPG AG and FEV GmbH are developing a range extender fuelled with compressed natural gas, and test its suitability for daily use

There are various concepts for electric vehicles, including one that targets the current problems with commercially available traction batteries. Traction batteries have the disadvantage of a low energy density compared with other energy sources or storage devices. Designing a sufficiently large battery is an option, but this leads to increased vehicle weights and manufacturing costs. The disadvantages are being increasingly offset by the installation of a classic combustion engine in the electric vehicle. In the case of a near-empty traction battery, the combustion engine supplies it with electrical energy via a driven generator. This increases the range of the vehicle, hence the name "range extender" for the internal combustion engine.

In a first step, the range extender developed by FEV and KSPG with its original petrol operation will be integrated into a StreetScooter commercial vehicle (model "Work") and presented to the public at the IAA Commercial Vehicles exhibition in Hannover. After that, the V2 KSPG range extender will be revised and optimised for operation with processed biogas by the Fraunhofer Institute in Karlsruhe, Germany, in close cooperation with FEV GmbH. The revised range extender will then be thoroughly checked on the test bench and afterwards integrated in another StreetScooter Work commercial vehicle.

The goal is a commercial vehicle that is operated solely with regenerative energy

The majority of existing range extenders consists of petrol SI engines. This is usually due to cost-efficient manufacturing. The obvious disadvantage of this concept is that the range extender is dependent on a fuel supply from crude oil. Engines for natural gas operation, that meet the requirements of a range extender, among them being low production cost, compact size and good NVH attributes, are currently not available.

The goal of the research project is to determine if a marketable vehicle that is completely operated with regenerative energy can be manufactured through a new combination of available mass production technologies. This includes the MOT approval, as well as first driving tests with documented CO2 savings for demonstration purposes and to illustrate the feasibility of the concept.

"The use of regeneratively produced methane as well as the easy storage of this fuel, for example in the natural gas network, is advantageous. Therefore methane complements conventionally generated energy sources in an ideal way," explains Professor Dr Stefan Pischinger, managing partner of the FEV Group Holding GmbH. "The project results yield the opportunity to offer low emission, light commercial vehicles with long ranges."

The “GreenREX” project is funded by the German Federal Ministry of Economics and Technology. Due to the early involvement of production specialists it is further expected that an estimate about the additional cost in comparison to the base variant can already be made by the end of the project.

About FEVThe FEV Group with headquarters in Aachen, Germany, is an internationally recognized development service provider for drive and vehicle technologies. The company offers its global transport industry customers a complete range of engineering services, providing support in the design, analysis and prototyping for powertrain and transmission development, as well as vehicle integration, calibration and homologation for advanced internal combustion gasoline-, diesel-, and alternative-fuelled powertrains. FEV's competencies also include design, development and prototyping of innovative vehicle concepts, powertrain electronic control systems and hybrid-electric engine concepts that address future emission and fuel economy standards. The Test Systems division is a global supplier of advanced test cell, instrumentation and test equipment. The FEV Group employs a staff of over 3,000 highly skilled specialists at advanced technical centres on three continents.